Study on behaviour of centrifugal pump driven by medium-voltage induction motor during operation control

Abstract

When studying electric drives, it is necessary to jointly analyze the processes in the electric power and control circuits of the electric motor as the main component determining the overall performance and in the mechanical executive part. The paper deals with the variation of the occurring torques, the currents flowing in the individual phases and the electrical power losses in the operation of a medium voltage electric drive of a pump unit from the point of view of energy efficiency. Emphasis is placed on the joint operation of the pump as a mechanism and the driving electric motor, studying the complete electromechanical system. During the studies, significant attention has been paid to the mathematical description and modeling with subsequent computer simulation of the ongoing electromagnetic and electromechanical processes. Different ways of controlling the motor have been applied - by softstarter and by frequency control. Also values for the duration of the start-up process have been obtained. Relevant conclusions have been drawn.